One vertex per element, one color per generator, with an edge from x to x·s.
(5,6,10,13)(7,14,16,11)(8,17,9,12)(15,19,18,20)(21,22,25,27)(23,31,33,36)(24,30,26,29)(28,34,35,32)(1,2)(3,4)(5,7,10,16)(6,11,13,14)(8,15,9,18)(12,19,17,20)(22,27)(28,35)(29,30)(31,36)(2,4)(21,23)(22,28)(24,32)(25,33)(26,34)(27,35)(29,31)(30,36) involution — undirected(5,8,10,9)(6,12,13,17)(7,15,16,18)(11,19,14,20)(22,27)(28,35)(29,30)(31,36)(2,4)(5,9,10,8)(6,12,13,17)(7,15,16,18)(11,20,14,19)(21,24,25,26)(22,29,27,30)(23,32,33,34)(28,31,35,36)A Cayley diagram is a choice, not a fact about the group. Another drawing of this group — in a book, or on a different generating set — may look nothing like this one.